Morgan
International Hazard
Posts: 1673
Registered: 28-12-2010
Member Is Offline
Mood: No Mood
|
|
Hydrogen from Methanol
Has anyone tried making hydrogen from methanol or does anyone know the details of this process?
http://www.springerlink.com/content/353364xq63px013x/
I once made some hydrogen by using bright magnesium in dry methanol, and even though it fizzed like an alka-seltzer, the stream of hydrogen was rather
paltry. Water in the methanol will slow the reaction greatly.Funny how powerful an agent the remaining fluid was, the Ice 9 of gelling agents if you
add water to it. I think it was some sort of cross-linked methoxide and hydroxide?
As I would be burning the methanol in a combustion chamber, I was hoping to use some of that heat to drive some kind of cracking reaction. Even a
small amount of hydrogen would help for what I want. I think the cracking goes best at around 300 C degrees but don't quote me.
Or if anyone knows a better way ...
|
|
|
NurdRage
Hazard to Others
Posts: 182
Registered: 11-11-2010
Member Is Offline
Mood: No Mood
|
|
If you just want hydrogen from methanol and don't really care how you go about doing it, or the rate, then look into electrolysis of methanol.
A solution of methanol and water (with some base as an electrolyte) will produce hydrogen and carbon dioxide.
CH3OH + H2O --> CO2 + 3H2
best of all the voltage requirements are lower than straight water splitting so you save power. Essentially you're "burning methanol" with water to
produce hydrogen and carbon dioxide.
Kinda like steam reformation of carbon to make hydrogen... except with methanol and at room temperature. 
I forgot what electrodes are needed though, i think it's fairly mild, like nickel or something.
I was actually going to make a video on this... Want to pitch in? 
[Edited on 15-2-2011 by NurdRage]
|
|
|
Morgan
International Hazard
Posts: 1673
Registered: 28-12-2010
Member Is Offline
Mood: No Mood
|
|
Yea, I read up on the electrolysis of methanol after I did the magnesium experiment. Just a little bit of water and the whole flask instantly gelled
and I worried my drain would clog. It was so thin and liquidy, the remaining methanol, methoxide, hydroxide mix, but with water in a blink turns to a
clear, very thick jelly.
I recall some guy going on and on about the lower voltages needed. I want to get something faster though, as in a pulsating combustion device. If I
could get 5% hydrogen into the methanol/air fuel ratio somehow, I would be happy.
[Edited on 15-2-2011 by Morgan]
|
|
|
Morgan
International Hazard
Posts: 1673
Registered: 28-12-2010
Member Is Offline
Mood: No Mood
|
|
I think this is the one I saw a few months ago.
Low Cost Hydrogen from Electrochemical Reforming
http://www.youtube.com/watch?v=ZZzW1cjxeb4
|
|
|
Morgan
International Hazard
Posts: 1673
Registered: 28-12-2010
Member Is Offline
Mood: No Mood
|
|
I was actually going to make a video on this... Want to pitch in?
It might be kind of interesting. Hydrogen is really perky though if you aren't careful and go to light it, if for example your flask has air in it and
isn't purged.
I always liked this demostration. Maybe rig this copper can up to the electrolysis of methanol device. ha
http://www.youtube.com/watch?v=ptiCFq5YK3Q
Or how about do the hydrogen and chlorine mix exposed to sunlight?
|
|
|
Random
International Hazard
Posts: 1018
Registered: 7-5-2010
Location: In ur closet
Member Is Offline
Mood: Energetic
|
|
If you just want easy hydrogen from magnesium I suggest you vinegar, it gives you nice and not very fast constant stream of H2 especially if it's not
powdered.
|
|
|
Morgan
International Hazard
Posts: 1673
Registered: 28-12-2010
Member Is Offline
Mood: No Mood
|
|
I guess there's no real way to crank out a reasonable amount of hydrogen easily. Even the hydrolysis guys on youtube have a huge amount of kluge just
to run a micro torch. It would be big business if you could do it cheaply.
The magnesium chunck of metal and vinegar might be fun to try, maybe make a variation on a theme using them to run a lighter like the Dobereiner Lamp,
where the metal is protected from the acid by a bubble of hydrogen, when the hydrogen is consumed the acid rises again into the bell.
I have some glacial acetic acid and powdered magnesium if I want something faster. I wonder though, like the methanol and magnesium run I did, if you
need a bright/unoxidized surface on the powder for the acid to attack the metal?
Here's a toy rocket that uses electrolysis.
http://www.i4u.com/10352/hydrogen-fuel-toy-rocket-sale
Methanol tidbit.
"The volumetric energy density of methanol is considerably higher than liquid hydrogen, in part because of the low density of liquid hydrogen of 71
grams/litre. Hence there is actually more hydrogen in a litre of methanol (99 grams/litre) than in a litre of liquid hydrogen, and methanol needs no
cryogenic container maintained at a temperature of -253°C."
http://en.wikipedia.org/wiki/Methanol_economy
I want hydrogen because it's less fussy in fuel/air mixtures. Engines that would normally run or run poorly might do much better with an added
percentage of hydrogen. Of course when you burn methanol you are burning hydrogen, it's just not as finely divided. (ha) I guess too, if you could
boost the oxygen content of the air, that would have the same effect as burning methanol enriched with hydrogen - getting the flame speed up.
I ran across an old chemistry book from around 1910 and it had an elegant demonstration and diagram using a spherical flask, a better presentation
than in this example, a theory of combustion which is interesting to recall, how the splitting of water changed a perspective, a death blow it said.
If you read pages 183-186, it's another good historical account/overview, the supporter of combustion becoming the combustible. It would make a good
video for youtube I think.
http://books.google.com/books?id=xnsAAAAAMAAJ&pg=PA284&a...
[Edited on 17-2-2011 by Morgan]
|
|
|
NurdRage
Hazard to Others
Posts: 182
Registered: 11-11-2010
Member Is Offline
Mood: No Mood
|
|
Are you looking for lots of different ways to make hydrogen? not just methanol reformation?
|
|
|
unionised
International Hazard
Posts: 5109
Registered: 1-11-2003
Location: UK
Member Is Offline
Mood: No Mood
|
|
I suspect we have a really long thread somewhere about making hydrogen from methanol.
The by-product is formaldehyde.
I'm sure I have seen a catalytic described method somewhere that improves on this and gives CO2 as the other product.
|
|
|
Random
International Hazard
Posts: 1018
Registered: 7-5-2010
Location: In ur closet
Member Is Offline
Mood: Energetic
|
|
If you try magnesium pencil sharpener in vinegar instead of powder, you will find it's slower, but it's more constant stream andit lasts longer. Once
I was filling baloons with that, the pencil sharpener was bubbling 15 minutes in vinegar and it wasn't used yet. Then I put it in strong citric acid
solution and it was dissolving few hours as I remember, but the hydrogen stream wasn't very slow.
|
|
|
Morgan
International Hazard
Posts: 1673
Registered: 28-12-2010
Member Is Offline
Mood: No Mood
|
|
I wasn't looking for every way to make hydrogen, but it occurred to me it would be an interesting topic, like your fire videos, if you did some
lesser known examples. I am though looking for the best way to make hydrogen cheaply and convenietly. Like with aluminum and NaOH, while relatively
inexpensive, it's still way too slow and messy. Since I would be burning methanol anyway, I was hoping I could use some of the heat to crack it as it
passed over a catalyst of some sort. But again, I want to keep it simple and not have to worry about byproducts as much as I can. If you preheat your
fuel, it burns a lot faster too, maybe I could dissociate methanol. ha
I have done the glowing platinum wire in methanol demo, in fact one time mine ran all through the night and the next morning it was still cycling with
a very weak intermittent whoosh, the methanol gets quite watery though. So also you can sustain a thin copper wire in methanol vapor if preheated. It
doesn't glow nearly as bright, more of a dull red, and it gets used/eaten up/melts fairly quickly. But I was wondering if a copper mesh would crack
methanol partially, perhaps formadehyde would burn faster than methanol? With both platinum and copper wire you can detect the incomplete combustion
with a formaldehyde odor.
I thought maybe it would be worth a try to use some copper mesh. I just want a bit more perkiness in my combustion, even a small conversion might
improve things.
"Formaldehyde is produced industrially by the catalytic oxidation of methanol. The most common catalysts are silver metal or a mixture of an iron and
molybdenum or vanadium oxides. In the commonly used formox process, methanol and oxygen react at ca. 250–400 °C in presence of iron oxide in
combination with molybdenum and/or vanadium to produce formaldehyde according to the chemical equation:[2]"
2 CH3OH + O2 → 2 CH2O + 2 H2O
The silver-based catalyst usually operates at a higher temperature, about 650 °C. Two chemical reactions on it simultaneously produce formaldehyde:
that shown above and the dehydrogenation reaction:
CH3OH → H2CO + H2
http://en.wikipedia.org/wiki/Formaldehyde
Here's some pure copper mesh I bought for various experiments. It was from a company that suggests it's use in a still as a heat exchanger and to
absorb sulfur compounds. ha
[Edited on 17-2-2011 by Morgan]
|
|
|
Random
International Hazard
Posts: 1018
Registered: 7-5-2010
Location: In ur closet
Member Is Offline
Mood: Energetic
|
|
Formaldehyde boils around -20 degrees celsius if it's pure, if you have azeotrope with water, then it's 37% solution which again won't be flammable I
think. So in my opinion, this seems a bit inpractical to do.
[Edited on 17-2-2011 by Random]
|
|
|
Morgan
International Hazard
Posts: 1673
Registered: 28-12-2010
Member Is Offline
Mood: No Mood
|
|
Quote: Originally posted by Random  | Formaldehyde boils around -20 degrees celsius if it's pure, if you have azeotrope with water, then it's 37% solution which again won't be flammable I
think. So in my opinion, this seems a bit inpractical to do.
[Edited on 17-2-2011 by Random] |
I was hoping to have an intake venturi that would jet methanol and air over a heated, high surface area copper mesh on it's way to my simple, no
moving parts jet engine toy. It's kind of a Reynst pulsating combustion device. It can pump/draw air and fuel through an intake, no help needed from a
fuel pump, pressure tank, etc. But yes, I am probably wanting something impractical and fishing with a slim chance of catching anything. I did run
across a copper/formadehyde topic today on this site when searching for more ideas. I've been reading about the topic here and there for quite awhile.
It just dawned on me a few months ago, everybody's trying to do it, make hydrogen from some source, even if it's from a fossil fuel, because nobody
likes storing liquid hydrogen if they don't have to. The fuel cell people tinker with methanol but you can bet they would like to crack it too.
[Edited on 17-2-2011 by Morgan]
|
|
|
Morgan
International Hazard
Posts: 1673
Registered: 28-12-2010
Member Is Offline
Mood: No Mood
|
|
Around the 12 minute mark to the 14 minute mark, it's kind of interesting how they use ethylene glycol for a fuel cell. At one point someone asks
about using ethanol, and he shoots that idea down.
Sub-ML Platin. Shell on Ruthenium-Core Nanoparticle Catalysts for Meth. & Ethylene Glycol Fuel Cells
http://www.youtube.com/watch?v=4btVPckvVN0
[Edited on 17-3-2011 by Morgan]
|
|
|
Morgan
International Hazard
Posts: 1673
Registered: 28-12-2010
Member Is Offline
Mood: No Mood
|
|
When I mixed a solid piece of magnesium metal with methanol, it forms hydrogen and the methoxide. But if you mixed a powdered magnesium with methanol
and then "shocked it", what would be the products of combustion? I recall reading this example below long ago and wondered if the air reacts with the
hydrogen released or if then the magnesium might use the H2O for a further reaction?
http://books.google.com/books?id=MH9DrW0UGvwC&pg=PA176&a...
I was dabbling with this simple thermite reaction with rusted iron balls and aluminum foil and wondered if powdered magnesium and a few drops of
methanol might pop or ignite like the impacting of rust and aluminum with a hard object.
Thermite Reaction - Smash! Bang! Boom!
http://www.youtube.com/watch?v=O5v3XxFfUOw
[Edited on 20-3-2011 by Morgan]
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
